For the most part, Electronic Flight Information Systems (EFIS) have replaced conventional aircraft electromechanical flight instruments for displaying primary flight and navigational data to an aircraft pilot or a member of the aircrew. EFIS systems present all information necessary for a current phase of flight in a compact display. An EFIS system typically includes an engine indication and crew alerting system (EICAS) display, a multi-function display (MFD), and a primary flight display (PFD).
The EICAS displays information about an aircraft's systems, such as the fuel, electrical systems, and propulsion systems. An EICAS display typically mimics conventional round (circular) gauges while supplying digital readouts of the measured parameters.
The EICAS improves situational awareness by allowing aircrew members to view complex information in a graphical format. The EICAS also can alert the aircrew members to unusual or hazardous situations. For example, if an engine begins to lose oil pressure, the EICAS can sound an alert (alarm), switch the display to the page with oil system information and outline the low oil pressure data with a red box. Unlike conventional round gauges, a user can set many levels of warnings and alarms.
The MFD displays navigational and weather information received from multiple systems. Typically, an MFD is “chart-centric”, where aircrew members can overlay different information over a map or chart. For example, MFD overlay information can include an aircraft's current route plan, weather information, restricted airspace information, and aircraft traffic information. The MFD can also view non-overlay types of data (e.g., current route plan) and calculated overlay types of data (e.g., the glide radius of the aircraft, given current location over terrain, winds, and aircraft speed and altitude).
As with the EICAS, the MFD can display information about aircraft systems, such as fuel and electrical systems. The MFD can improve a pilot's situational awareness by changing the color or shape of the data to alert aircrew members to hazardous situations (e.g., low airspeed, high rate of decent, terrain warnings).
The PFD displays all information critical to a flight, including airspeed, altitude, heading, attitude, vertical speed and yaw. The PFD improves a pilot's situational awareness by integrating this information into a single display instead of six different analog (conventional) instruments, thereby reducing the amount of time necessary to monitor the instruments.
As with the MFD, the PFD increases situational awareness by alerting aircrew members to unusual or potentially hazardous conditions by changing the color or shape of the display and/or by providing audio alerts.